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<H1>is_handle(?Term)</H1>
Succeeds if Term is an external data handle.


<DL>
<DT><EM>Term</EM></DT>
<DD>Prolog term.
</DD>
</DL>
<H2>Description</H2>
   Used to test whether Term is a handle for external data.
   Such handles can be created by external predicates using the
   ECLiPSe C or C++ API.

<P>

<H3>Modes and Determinism</H3><UL>
<LI>is_handle(?) is semidet
</UL>
<H3>Fail Conditions</H3>
Fails if Term is not an external data handle
<H2>Examples</H2>
<PRE>

    ?- bag_create(B), is_handle(B).
    B = 'BAG'(16'edc90b18)
    Yes (0.00s cpu)

    ?- is_handle(_).
    No (0.00s cpu)

    ?- is_handle(42).
    No (0.00s cpu)

</PRE>
<H2>See Also</H2>
<A HREF="../../kernel/typetest/is_event-1.html">is_event / 1</A>, <A HREF="../../kernel/typetest/type_of-2.html">type_of / 2</A>, <A HREF="../../kernel/externals/xget-3.html">xget / 3</A>, <A HREF="../../kernel/externals/xset-3.html">xset / 3</A>
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